Silver is notoriously slow ...
Published by Joseph Cotruvo, President at Joseph Cotruvo & Associates, Water , Environment and Public Health
4 Comments
To reiterate, one should not say that silver is slow acting without describing how the ceramic filter was designed and how it was treated with silver. Or at least tell how produced the filters and what claims the made.
There are many ways of combining the variables of ceramic filter production and only if done improperly is the silver slow acting at reducing pathogens. To be scientifically responsible one must give the details of the ceramics, and not only the details of the pathogen reduction!
Published by Anthony Reid Harvey
Not to belabor the point, but the following posting was published through the WHO, by the UNC Water Institute hosted, Household Water Network, Newsletter no. 52: http://hwts.web.unc.edu/2019/01/29/household-water-newsletter-issue-51-2/
The following posting is found scrolling down to the header, *Publications*
Filtering Safe Drinking Water through Granulated Ceramics
The world is thirsty for safe drinking water. But too many do not have access, especially in developing regions. Silver-treated ceramic granule filters offer an affordable, sustainable option for purifying water in households, and even on municipal scales. Find this article by Harvey et al. (TAM Ceramics) here, and for further information, contact rharvey@tamceramics.com.
Published by Anthony Reid Harvey
A further reason why silver is remarkably effective against pathogens in granulated ceramic media is that there is a huge amount of surface area on the combined granules. This far exceeds that surface area that's typical of monolithic ceramic filters.
Published by Anthony Reid Harvey
The WHO report on silver is outdated and not well informed. If silver is slow acting it would have a lot to do with the amount of it, numbers of silver contacts and the residence time of pathogens. This and doubts about efficacy with particular pathogens indicate insufficient study.
Published by Anthony Reid Harvey